TY - JOUR
T1 - High spin polarization and spin splitting in equiatomic quaternary CoFeCrAl Heusler alloy
AU - Bainsla, Lakhan
AU - Mallick, A. I.
AU - Coelho, A. A.
AU - Nigam, A. K.
AU - Varaprasad, B. S.D.Ch S.
AU - Takahashi, Y. K.
AU - Alam, Aftab
AU - Suresh, K. G.
AU - Hono, K.
N1 - Funding Information:
One of the authors, LB would like to thank UGC , Government of India for providing the senior research fellowship. AIM acknowledges the support from TAP fellowship under SEED Grant (Project code 13IRCCSG020 ). KGS thanks ISRO , Govt. of India for the funds for carrying out this work. Authors thank D. Buddhikot, TIFR for his help in magneto-transport measurements.
Publisher Copyright:
© 2015 Published by Elsevier B.V.
PY - 2015/6/29
Y1 - 2015/6/29
N2 - In this paper, we investigate CoFeCrAl alloy by means of ab-initio electronic structure calculations and various experimental techniques. The alloy is found to exist in the B2-type cubic Heusler structure, which is very similar to Y-type (or LiMgPdSn prototype) structure with space group F-43m (#216). Saturation magnetization (MS) of about 2 μB/f.u. is observed at 8 K under ambient pressure, which is in good agreement with the Slater-Pauling rule. MS values are found to be independent of pressure, which is a prerequisite for half-metals. The ab-initio electronic structure calculations predict half-metallicity for the alloy with a spin slitting energy of 0.31 eV. Importantly, this system shows a high current spin polarization value of 0.67±0.02, as deduced from the point contact Andreev reflection measurements. Linear dependence of electrical resistivity with temperature indicates the possibility of reasonably high spin polarization at elevated temperatures (∼150 K) as well. All these suggest that CoFeCrAl is a promising material for the spintronic devices.
AB - In this paper, we investigate CoFeCrAl alloy by means of ab-initio electronic structure calculations and various experimental techniques. The alloy is found to exist in the B2-type cubic Heusler structure, which is very similar to Y-type (or LiMgPdSn prototype) structure with space group F-43m (#216). Saturation magnetization (MS) of about 2 μB/f.u. is observed at 8 K under ambient pressure, which is in good agreement with the Slater-Pauling rule. MS values are found to be independent of pressure, which is a prerequisite for half-metals. The ab-initio electronic structure calculations predict half-metallicity for the alloy with a spin slitting energy of 0.31 eV. Importantly, this system shows a high current spin polarization value of 0.67±0.02, as deduced from the point contact Andreev reflection measurements. Linear dependence of electrical resistivity with temperature indicates the possibility of reasonably high spin polarization at elevated temperatures (∼150 K) as well. All these suggest that CoFeCrAl is a promising material for the spintronic devices.
KW - Half metallic ferromagnet
KW - Heusler alloys
KW - PCAR
KW - Spintronics
KW - ab-initio calculation
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U2 - 10.1016/j.jmmm.2015.05.095
DO - 10.1016/j.jmmm.2015.05.095
M3 - Article
AN - SCOPUS:84933037592
SN - 0304-8853
VL - 394
SP - 82
EP - 86
JO - Journal of Magnetism and Magnetic Materials
JF - Journal of Magnetism and Magnetic Materials
ER -